Derivatization method of qualitative or quantitative analysis for polyhydroxy compound

Abstract

The invention discloses a derivatization method for polyhydroxy compound. In the method, a sugar-containing sample is disposed in a reaction system using 1-methylimidazole as catalyst and acetic anhydride as derivatization reagent to have acetylation derivatization reaction. The method in the invention can carry out acetylation derivatization on the basis of maintaining native conformation of sugar, single derivatization product is obtained after derivatization, and qualitative or quantitative analysis can be accurately carried out on various simple sugars.

Description

technical field [0001] The invention relates to a derivatization method of polyhydroxyl compounds, in particular to an acetylation derivatization method for qualitative or quantitative analysis of polyhydroxyl compounds. Background technique [0002] The monosaccharides existing in nature can be divided into neutral monosaccharides (aldose and ketose), acidic monosaccharides (uronic acid), sugar alcohols, sugar amines and thiosugars, etc., which are analyzed by gas chromatography Occasionally, derivatization is required due to the presence of its hydroxyl groups. At present, the methods commonly used for the derivatization of monosaccharides mainly include methyl silylation (trimethyl silylation), acylation (sugar oxime acetylation and sugar alcohol acetylation) and methylation. Among the currently commonly used monosaccharide derivatization methods, the silanization method requires a strict anhydrous operating environment to prevent experimental failure because the derivat...

AI Technical Summary

Problems solved by technology

This method can be better used for the derivatization analysis of aldose and sugar alcohol, but for ketose, fructose, etc., it cannot be effectively oximated and derivatized, because hydroxylamine hydrochloride cannot completely oximate the ketone group, resulting in Not a single but multiple product coexistence phenomenon (such as figure 2 ) makes this method unable to detect ketose

[0006] 2. There are problems in the mechanism of acetylation derivatization of sugar alcohols

[0007] This method has a good acetylation derivatization effect on sugar alcohols, but for aldose and ketose, it needs to be reduced to the corresponding sugar alcohol with sodium borohydride before derivatization, resulting in the inaccurate analysis and determination of ketose , aldose and alcohol sugars exist at the same time

[0008] (1) Aldose problem: use sodium borohydride to reduce the aldehyde group or ketone group of the sugar to a hydroxyl group, and then acetylate it

Since the aldose-reduced sugar alcohols cover up the sugar alcohols that actually exist in nature and have important physiological functions, it not only makes it impossible to accurately determine the natural aldose content, but also directly leads to the inability to detect these naturally occurring sugar alcohols

[0009] (2) Ketose problem - this method cannot directly detect ketose

[0012] 2. Commonly used derivatization methods have problems in derivatization reaction conditions --- high temperature requirements, long time, and inappropriate reaction solvents

[0017] 2. Commonly used derivatization methods require reaction time

[0020] 3) In the sugar alcohol acetylation method, the sodium borohydride reduction reaction needs at least 60-90 minutes, and there are many reaction steps and chemical reagents, wasting valuable time [Blakeney A.B., Harris P.J., Henry R.J.and Stone B.A. (1983) A simple and rapid preparation of alditol acetates for monosaccharide analysis. Carbohydrate Research 113, 291-299.〕

[0021] 3. The problem of solvents used in common derivatization methods

[0022] Need to use anhydrous pyridine as reaction solvent in the silanization method, and isomerization phenomenon (such as Figure 7 ), a phenomenon of multiple chromatographic peaks of monosaccharides appears during chromatographic separation, which affects the qualitative and quantitative analysis of monosaccharides

[0023] 3. Problems in the stability of commonly used derivatization reagents and derivatization products

This method is greatly affected by moisture, and needs to be operated under strict anhydrous conditions, otherwise the methyl silylation reagent and its derivative products are easily degraded by water, which will affect the authenticity of the analysis results [Marie-christineet. (1997) Determination of Carbohydrates in two ferrlitic soil: analysis by capiliary gas chromatography after derivatization by silylation.SoilBiol.Biochem.Vol.29, No.9/10, pp.1585-1589〕

[0026] 2) In the sugar alcohol acetylation method, sodium borohydride is easy to absorb moisture and deteriorate, and the storage conditions are relatively high

[0027] 4. Problems in the qualitative and quantitative analysis of monosaccharides by common derivatization

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